1. Field of the Invention
This invention relates to a composition and process for treating the surface of aluminum objects to improve their resistance to corrosion, either as treated, or more particularly after subsequent painting or similar coating with an organic protective layer. The invention is applicable to any surface that consists predominantly of aluminum (hereinafter denoted as an "aluminous surface") and is especially suited to various commercial aluminum alloys, such as Types 3003, 3004, 3104, 3105, 182, 5050, and 5352, but is not limited to these particular alloys. The composition of the invention is substantially or entirely free from chromium and therefore less polluting than the now common commercial chromating treatment for the same purpose.
2.Statement of Related Art
Numerous compositions and processes for treating aluminous surfaces are currently known in the art. Where maximum corrosion protection of aluminous surfaces is dechromium containing surface treatment compositions with an associated pollution potential.
The prior art which is believed most closely related to the present invention is that teaching surface treatment of metals with polymers of vinyl phenols. The phenols optionally have various additional functional groups on the aromatic rings of the polymer, including amine and substituted amine groups. U.S. Pat. No. 4,517,028 of May 14, 1985 to Lindert et al. is an example of this related prior art.